To improve the peak rate and user experience of a user, a network side (data sending end) usually sends data to a terminal (data receiving end) without limiting on a carrier/process.
Accordingly, the data receiving end needs to send HARQ information to the data sending end, namely feeds a result indicating whether data on each carrier/process is correct back. If detection is correct, an Acknowledgement (ACK) will be fed back. Otherwise, a Negative Acknowledgement (NACK) will be fed back.
In an existing 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) system, the terminal needs to feed HARQ information back according to the number of carriers configured and a transmission mode of each carrier by the network side. If the transmission mode of the carriers is a spatial multiplexing mode, each carrier needs to feed 2-bit HARQ information back. Otherwise, each carrier needs to feed 1-bit HARQ information back. For example, the network side configures five carriers for the terminal, and a transmission mode of each carrier is a spatial multiplexing mode, then, the terminal needs to feed 10-bit HARQ information back to a network on an uplink sub-frame. If the carriers are Time Division Duplexing (TDD) carriers, the terminal also needs to configure HARQ information according to uplink and downlink configurations of the carriers. Suppose that the network configures a TDD carrier for the terminal and an uplink and downlink configuration of the carrier is a configuration 5, the terminal needs to feed HARQ information (9 bits) of nine downlink sub-frames back on an uplink sub-frame. Likewise, if the network configures two TDD carriers for the terminal, and uplink and downlink configurations of the carriers are configurations 5, the terminal needs to feed HARQ information (18 bits) of 18 downlink sub-frames back on an uplink sub-frame. The number of carriers and the number of downlink sub-frames in the above-mentioned examples are a resource range of data probably sent to the terminal by the network side. Actually, due to the reasons of network loads, carrier availability and the like, at most situations the network side may send data to the terminal over some resources within the resource range. When the resource range configured by the network side is very large and there are few available resources that are used in the actual sending, the terminal still feeds the HARQ information back according to resources configured by the network side, then the following problems will be caused: many bits that are fed back are unavailable, thus not only increasing the overhead, but also reducing the performance of available bits; if the power is increased to ensure the performance of the available bits, the intra-system interference is also increased equivalently. A method for solving the above-mentioned problem is that: the terminal conducts HARQ feedback according to detected actual situations, but this also causes another problem: since the reliability of a physical layer control signaling indicating data transmission is much lower than the reliability of high-layer configuration information, this feedback mode may cause that the network cannot correctly understand the HARQ information fed back by the terminal. For example, the network sends data to the terminal over a resource 0, a resource 1 and a resource 2. However, due to the reasons such as a channel, the terminal does not correctly receive the physical layer control signaling indicating data transmission over the resource 0 and the resource 1. In this case, the terminal only feeds HARQ information corresponding to the resource 2 back to the network. After receiving the information, the network side does not know which resource the HARQ information belongs to.
Any effective solution has not been proposed yet at present for the above-mentioned problem.